Blender Cycles smoke won't render
Smoke rendering in Cycles still has a few tricks:
1- Quick smoke should have created some default shaders for the Smoke Domain, make sure they are there, if not recreate them like this:

Note that the attributes are written in lowercase. Using uppercase will make the materials fail
2- As of version 2.77 Smoke can be rendered using GPU

For blender versions prior to 2.77 you can only use CPU rendering to be able to see the smoke in render view and in the final render.



Rendered Image:

For a detailed description of nodes for Fire+Smoke on cycles read: Rendering smoke in Cycles?